U.S. patent application number 14/232182 was filed with the patent office on 2014-05-22 for method and communication system for data reception in wireless vehicle-to-surroundings communication.
The applicant listed for this patent is Marc Menzel, Richard Scherping, Ulrich Stahlin. Invention is credited to Marc Menzel, Richard Scherping, Ulrich Stahlin.
Application Number | 20140140353 14/232182 |
Document ID | / |
Family ID | 46466491 |
Filed Date | 2014-05-22 |
United States Patent
Application |
20140140353 |
Kind Code |
A1 |
Stahlin; Ulrich ; et
al. |
May 22, 2014 |
Method and communication system for data reception in wireless
vehicle-to-surroundings communication
Abstract
A communication system of a vehicle receives data in wireless
vehicle-to-surroundings. The communication system includes multiple
control devices. A receiving control device receives data from
objects located in the surroundings of the vehicle, and a
communication stack is processed during reception. In order for the
data to be expediently and effectively acquired, the received data
is sorted into at least two classes of relevance and is further
processed in the communication stack according to the class of
relevance.
Inventors: |
Stahlin; Ulrich; (Eschborn,
DE) ; Menzel; Marc; (Weimar (Lahn), DE) ;
Scherping; Richard; (Liederbach am Taunus, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Stahlin; Ulrich
Menzel; Marc
Scherping; Richard |
Eschborn
Weimar (Lahn)
Liederbach am Taunus |
|
DE
DE
DE |
|
|
Family ID: |
46466491 |
Appl. No.: |
14/232182 |
Filed: |
June 29, 2012 |
PCT Filed: |
June 29, 2012 |
PCT NO: |
PCT/EP2012/062682 |
371 Date: |
January 10, 2014 |
Current U.S.
Class: |
370/419 |
Current CPC
Class: |
B60W 2050/0043 20130101;
H04L 67/12 20130101; H04L 45/42 20130101; H04L 45/3065 20130101;
H04L 67/327 20130101; B60W 2556/65 20200201; H04L 67/322
20130101 |
Class at
Publication: |
370/419 |
International
Class: |
H04L 12/725 20060101
H04L012/725; H04L 12/717 20060101 H04L012/717 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 12, 2011 |
DE |
10 2011 107 111.7 |
Claims
1-15. (canceled)
16. A method for data reception in wireless vehicle-to-surroundings
communication in a communication system (1) of a vehicle (F) with a
plurality of control devices (2, 3, 4, 18), the method comprising:
receiving, by a receiving control device (2), data from objects (O)
from the surroundings of the vehicle (F); during the receiving,
processing a communication stack; sorting the received data into at
least two different classes of relevance; and further processing
the communication stack depending on the class of relevance from
the sorting step.
17. The method as claimed in claim 16, wherein the further
processing of the received data takes place on different control
devices.
18. The method as claimed in claim 16, wherein the received data
are allocated to different applications according to the class of
relevance.
19. The method as claimed in claim 16, wherein a distance between
the object (O) and the vehicle (F) is allocated to the received
data of an object (O) and the sorting into the classes of relevance
is carried out on the basis of the distance.
20. The method as claimed in claim 16, wherein a time-to-collision
is allocated to the received data of an object (O) and the sorting
into the classes of relevance is carried out on the basis of the
time-to-collision.
21. The method as claimed in claim 16, wherein the sorting of the
received data of objects (O) is carried out on the basis of overlap
with a coverage area of one or more environment sensors of the
vehicle (F).
22. The method as claimed in claim 16, wherein a priority is
allocated in each case to a class of relevance and the further
processing in the communication stack is dependent on this
allocated priority.
23. The method as claimed in claim 16, wherein quality of the
received data is improved on the basis of data of a different
object (O) or of a sensor.
24. The method as claimed in claim 16, further comprising carrying
out a dynamic prediction of an object (O) participating in the
vehicle-to-surroundings communication.
25. The method as claimed in claim 16, further comprising
determining, from the data of an object (O), a trajectory of the
object (O) and extrapolating this trajectory.
26. The method as claimed in claim 16, wherein the data of objects
(O) are combined into groups (G).
27. The method as claimed in claim 26, wherein a group (G) is
represented by the object (O) with the lowest time-to-collision
and/or with the shortest distance to the vehicle (F).
28. The method as claimed in claim 16, wherein three classes of
relevance are formed.
29. A communication system for data reception in wireless
vehicle-to-surroundings communication between individual
communication participants, the communication system (1) being
provided in a vehicle (F) and comprising: a plurality of different
control devices (2, 3, 4, 18); and a plurality of computing units
each associated with respective one of the plurality of different
control devices, wherein the computing units of the control devices
(2, 3, 4, 18) are configured to carry out the method as claimed in
claim 16.
30. A non-transitory computer-readable medium storing computer
program code, which, when executed on a computing unit of a control
device of a vehicle, causes the control device to carry out the
method as claimed claim 16.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a U.S. national stage of application No.
PCT/EP2012/062682, filed on 29 Jun. 2012, which claims priority to
the German Application No. 10 2011 107 111.7, filed 12 Jul. 2011,
the content of both incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a method for data reception in
wireless vehicle-to-surroundings communication (C2X), in particular
mobile vehicle-to-surroundings communication or vehicle-to-vehicle
communication (C2C) as a special case of C2X communication, in a
communication system of a vehicle with a plurality of control
devices in which a receiving control device receives data from
objects from the surroundings of the vehicle and in which, during
the reception of the data, in at least one control device, but
preferably in a plurality of control devices of the vehicle, a
communication stack is processed, and also a correspondingly
configured communication system of the vehicle.
[0004] 2. Related Art
[0005] A vehicle communication system of this type usually consists
of a plurality of control devices which perform different
functions. In the vehicle, the data physically received by one or
more antennas with one or more allocated receivers (or combined
transmitters and receivers) are further processed by the one
control device or the plurality of control devices of the
communication system. Typically, one of the control devices, which
is also referred to in the context of this application as a
receiving control device, will contain the transmitting and
receiving part and parts of the communication stack to be
processed, which will be explained in somewhat more detail below.
At least one control device is then provided for the actual
application, for example a driver assistance function. Further
parts of the communication stack, for example with the facility
layer, may also be located in still further, different control
devices of the vehicle.
[0006] The reception process and the tasks of the control devices
performed therein are controlled by the so-called communication
stack. The C2X communication stack or the associated C2X
communication protocol describes, with reference to the OSI model,
the tasks which are performed in mobile C2X communication. This
communication stack is largely standardized in Europe by an
industry cooperation of the C2C Communication Consortium (C2C-CC)
and the ETSI and/or the CEN. In the USA, the standardization is
carried out by e.g. IEEE, SAE, etc. The tasks to be carried out by
the communication stack may, in particular, be the (physical) data
reception, the routing of the data, the processing of the data
between the reception and the application or the provision of data
in the vehicle. These tasks are performed according to the
specifications in different layers of the OSI model.
[0007] In C2X communication, data are exchanged between the vehicle
(C) and objects in its surroundings (X). The objects in the
surroundings may be permanently installed transmitting units by the
side of the road, referred to as Road Side Units (RSU), other
vehicles participating in the traffic or standing idle, or
pedestrians equipped with corresponding transmitters and/or
receivers. The exchanged data perform different functions, for
example a protection, warning and/or information function, and can
also be used by a driver assistance system.
[0008] In C2X communication, depending on the traffic density or
density of transmitters participating in the C2X communication, the
exchange of large data volumes may occur, so that the bandwidth
available in the physical radio band for the communication is
heavily loaded. It is known that bandwidth is a limiting factor in
the transmission and/or reception of data. Exhaustive use of the
bandwidth can result in time delays to the point of a breakdown of
the communication network. However, in the case of the
safety-related applications of the mobile C2X communication, the
data exchange can be extremely time-critical, since the traffic
situation of a moving vehicle, where appropriate, changes quickly
and a warning is intended to be given in good time before a
dangerous situation. At the same time, the dangerous situation
itself often changes also. It is therefore necessary for the
communication system of a vehicle to record and further process the
information exchanged in the C2X communication quickly. The volume
of information represents a major problem here.
[0009] US 2003/0139881 A1 shows a method for operating a pre-crash
sensing system for a vehicle by means of C2X communication, which,
following a first check, allows communication with specific objects
only. To do this, a pre-crash sensing system determines the
proximity or distance between the one own vehicle and the other
vehicle serving as a possible communication partner. If the
vehicles are located in their mutual field of view, a key is
exchanged and communication is started. As a result, only vehicles
which could potentially represent a danger to one another
communicate with one another. The data volume is thereby reduced
compared with a communication solution in which all vehicles in a
predefined surrounding area would communicate with one another.
However, it is disadvantageous that, due to the checking of a
hazardous situation and subsequent key exchange, the communication
becomes more complex and the establishment of communication takes
longer. In the case of a critical situation, this can result in
problematic delays. This type of establishment of communication
also results in an increase in the exchanged data volume,
particularly also in time-critical dangerous situations. This
partially cancels out the described advantage in the selection of
information and can, for its part, result in time delays.
[0010] WO 2006/015747 A1 shows a preventive protective system with
which the features from the multiplicity of input variables of the
safety sensor system relevant to the safety of the motor vehicle
are filtered out. The preventive protective system of the motor
vehicle acts preventively in that the safety sensor system is
controlled depending on preselected features. It is proposed, for
example, to allocate a specific weighting, in terms of criticality,
to features indicating a frontal impact. This system accordingly
describes a specific filtering for a specific dangerous situation.
However, no distinction is made here as to whether a danger could
or could not arise at all from a detected object. Moreover, the
features must be defined in advance, so that this case is not
appropriately applicable to a complex and variable C2X
communication with many different participants.
[0011] In mobile C2X communication, extremely large data volumes
can occur, which must be processed quickly and completely, as they
are otherwise worthless. There is the additional hindrance that not
every control device of the communication system can process all
data. In particular, safety-related data should only be processed
by control devices which have a low probability of failure. The
probability of failure is indicated here by the so-called ASI
level, which is defined in detail in ISO 26262.
SUMMARY OF THE INVENTION
[0012] The object of the invention is to propose a possibility for
recording the received data expediently and effectively.
[0013] According to a first aspect of the present invention, the
data received in the vehicle are sorted into at least two different
classes of relevance and processed in the communication stack
depending on the class of relevance. The dependence can, in
particular, consist in that data from different classes of
relevance are further processed differently. As a result, the
potentially large volume of received data is preprocessed so that
not all elements of the processing chain in the communication stack
are burdened with unnecessary, i.e. irrelevant, data.
[0014] Since not every type of processing of data is allowed in any
given control device, because, for example, specific safety-related
data can be processed only in control devices with the
corresponding safety level, it is proposed according to an aspect
of the invention to distribute the proposed preprocessing in
particular among different control devices also, wherein, between
the different steps of the preprocessing, further parts of the
communication stack, preferably the normal communication stack
without the preprocessing according to the invention, can also be
processed. The check on the relevance of the data received from
other objects can essentially be carried out in any control device.
The sorting into classes of relevance then decides whether these
data are further processed at all, and in what way they are further
processed.
[0015] It is therefore preferred according to an aspect of the
invention to carry out the sorting of the data directly in the
control device designed for the reception, wherein this receiving
control device can also be, and also normally is, simultaneously
designed for the transmission of data. As the relevance check takes
place directly in the receiving control device, this can be carried
out particularly comprehensively and quickly, since all data from
the surroundings are received by the receiving control device and
the sorting of the data into classes of relevance is preferably
carried out exclusively using the received data. No delay due to a
complex communication between the vehicle and its surroundings or
due to an elaborate evaluation of the data therefore occurs. In
particular, the solution according to the invention requires no
multiple transmission and reception between the object and the
vehicle, for example to exchange a security key.
[0016] The direct sorting of the received data into classes of
relevance by the receiving control device allows the available
resources to be used effectively, since it is subsequently already
possible to process the classes of relevance in the communication
stack and, where appropriate, a plurality of downstream control
devices in different ways. Thus, for example, the application to
which the data are to be forwarded can be determined based on the
class of relevance, so that the data processing according to the
invention can also be distributed among different control devices.
The further processing of the data can therefore take place
according to the invention on different control devices, wherein,
where appropriate, the same data can also be further processed on
different control devices. It is furthermore possible to sort the
data into different applications according to the class of
relevance.
[0017] Similarly, it is thus possible to remove data and therefore
prevent downstream parts of the communication stack from being
burdened with unnecessary data, since the processing time for
relevant data can also be significantly reduced through the removal
of irrelevant data.
[0018] In a particularly simple embodiment, only two classes of
relevance, i.e. relevant and irrelevant, can be provided, wherein
only the data sorted into the "relevant" class of relevance are
further processed and the other received data are rejected.
[0019] According to one aspect of the invention, the interval or
distance between the object and the vehicle can be selected as the
criterion for the division into the class of relevance. This is,
for example, simply possible because the data telegrams exchanged
in the C2X communication contain a position indication of the
transmitter, for example in the coordinates of a predefined
coordinate system such as a satellite-based location system. This
information is therefore available immediately following the
reception of the data telegram.
[0020] The location and position information of the own vehicle is
often present in the receiver or the control device directly
allocated to it (receiving control device), since this receiving
control device, for example, also evaluates the satellite data
telegrams of a satellite-based location system, and/or because this
receiving (and also transmitting) control device allocated to the
receiver and transmitter of the vehicle provides the data telegrams
of the C2X communication transmitted by the vehicle with the
position information also made available to it, where appropriate,
in real time and continuously by other control devices. The
distance between the objects can be derived simply and quickly from
this position information present in the same coordinate system
also, wherein the distance simply represents the linear distance
between the objects. However, road or direction information does
not (yet) need to be taken into account here, even if this is
essentially already possible, in particular for the own
vehicle.
[0021] In a further aspect, the sorting into the classes of
relevance takes place alternatively or additionally, using a
collision time allocated to the data received in the vehicle in the
receiving control device. The distance (for example in relation to
the linear distance or the actual instantaneous movement direction)
and the relative speed between the object and the vehicle, can be
used in a simple manner to determine the collision time, also
referred to as the "time-to-collision" or TTC for short. The
relative speed indicates how quickly the object from which the data
are first transmitted is moving in relation to the receiver of the
data. Alternatively, it would also be possible, based on the
location and speed of the own vehicle and of the object, to define
collision ranges which supply their maximum range in a predefined
time-to-collision. If overlaps in these collision ranges occur, the
time-to-collision is understepped.
[0022] In a further aspect of the method according to the
invention, the sorting of the received data from objects is carried
out on the basis of the overlap with the coverage area of one or
more environment sensors of the vehicle. It may thus be
appropriate, for example, to divide data of this type into a class
of relevance that allows a dynamic prediction of the data in order
to support and/or speed up the evaluation by the environment
sensor.
[0023] According to a further aspect of the present invention, a
priority can be allocated to a class of relevance. A different
priority can preferably be allocated to different classes of
relevance. It is also possible to allocate different priorities to
data or the associated objects in a class of relevance in the sense
of a division according to importance of the data in order to sort
the received data according to their importance within a class of
relevance also. A high priority is advantageously allocated to data
with a short time-to-collision, i.e., a possible potential
collision in a short time relative to the current time. These
higher-priority data are then given preferential treatment in the
further processing of the data in the communication stack or by
individual control devices, wherein different priorities can also
preferably be allocated to the data from different classes of
relevance. The lower-priority data are not neglected or rejected,
but processed only with a delay and/or in different ways in the
communication stack and/or in different control devices compared
with higher-priority data. A further important advantage of the
prioritization is that the processing of classes of relevance
and/or data with the highest priority can be controlled in such a
way that the latter are carried out only in control devices with a
corresponding ASI level.
[0024] According to an appropriate further aspect of the invention,
it can be provided in the method that the quality of the received
data is improved by the data of a different object or of a sensor.
For this purpose, a validation of the received data or data derived
therefrom can preferably be carried out in a next control device
downstream of the receiving control device, in particular using
additional vehicle data. A filtering out of invalid data and an
increase in the reliability of the remaining data can thereby be
achieved. To carry this out, the control device or, where
appropriate, a plurality of different control devices, can collect
and process not only data received from the surroundings in the C2X
communication, but also data from vehicle sensors. A sensor data
fusion can also be carried out here. In a sensor data fusion, data
which are received from different sensors can be linked with one
another in order to improve the quality of the data or information
through reference to different data sources and sensor sources.
This is advantageous, in particular, if the sensors have different
modes of operation, since these sensors then normally have
different systematic errors, and the total error is then improved
through a combination of the different sensor data. Quality of data
is understood, in particular, to mean the reliability, accuracy
and/or density of the data. It is thus possible, inter alia, to
obtain a more precise distance measurement if, for example, a data
fusion takes place between the location information from data of
the C2X communication and from data of a radar sensor such as the
environment sensor located in the vehicle. Different sensors of the
vehicle or data already derived therefrom can be used in the sensor
data fusion. In particular, data retrievable by other vehicle
control devices as information in the vehicle communication system,
preferably a bus system, are advantageous here, since they can be
picked up simply by each control device in a step of the stepwise
preprocessing according to the invention of the received data.
[0025] It is similarly possible according to the invention, in a
specific step of the preprocessing according to the invention, to
carry out a dynamic prediction of objects participating in the C2X
communication, i.e., in particular other vehicles. A dynamic
prediction involves the prediction of the future data of an object,
in particular relative to the particular (receiving) vehicle. An
important subsidiary aspect thereof is the determination of the
future position data of an object. For this purpose, it is provided
to record and subsequently extrapolate the speed and/or position of
a vehicle by the mobile C2X communication and/or in a sensor data
fusion. Sensor data of the vehicle and data from the mobile C2X
communication are generally used here in order to project existing
data into the future and thus anticipate a traffic situation.
[0026] In a further development of this idea according to the
invention, a trajectory of the object can be determined from the
data present for the object, and this trajectory can be
extrapolated, the extrapolation being based in particular on the
data received in the C2X communication, where appropriate
incorporating other sensor data. A statement on a future traffic
situation is thereby possible. In the case where sufficient time
and/or resources, in particular computing time, are available in a
control device, an extrapolation is preferably determined using a
map and the expected route. The distance information can hereby
also be qualitatively improved by distance information adapted to
the map.
[0027] In road traffic, vehicles are frequently in comparable
situations. Thus, for example, vehicles normally travel alongside
and behind one another at different speeds in the lanes on
highways, wherein greater speed differences normally occur in the
passing lanes only if the traffic density is not too high. In the
case of higher traffic density, a convoy formation frequently
arises with a convoy speed, in particular in the event of
congestion or slow-moving traffic. Speeds lower than would be
structurally possible, and therefore convoy formation, can also
occur in traffic due to weather influences or speed restrictions.
The same applies in the case of roadwork. Also in the case of entry
and exit slip roads, dividing or merging roads, reduction or
expansion on highways, a group of vehicles traveling one behind the
other usually reveals a similar movement pattern. It is similarly
possible that the vehicles are located at a known, marked traffic
location, such as a junction, intersection, railway crossing or
traffic lights, on a rural road or in urban traffic.
[0028] In such situations, the objects are characterized by
homogeneous data, i.e. the data of the different objects are
similar or identical. These data are therefore characterized by a
low variance around their average, and an individual object can
already clearly describe the characteristic of such a group of
objects. In such a case, it can be provided according to an aspect
of the invention to combine the data from objects, in particular
objects within a class of relevance, into groups. All objects in
such a group therefore resemble one another in their traffic
behavior, so that the data of this group of vehicles can be
combined. This is preferably not done in the receiving control
device, but in a downstream control device. This method variant is
then particularly economical on resources. A reduction of the data
volume is therefore carried out according to the invention by
combining the different objects into a group or an event to be
processed in the data-processing.
[0029] A convoy speed, for example, and the length and location of
the group can be transferred as important group parameters. The
length or extension of the group can, for example, be determined as
the total quantity of the positions of the individual objects or as
their center point or focal point. The convoy speed can preferably
also be formed as the mean value of the speeds of the objects
combined in the group. In addition, the object next to the own
vehicle can also be transferred as an individual object which will
then, for example, also be accessible to a dynamic prediction.
Instead of the aforementioned group parameters, the parameters of
this next object from the group can also be used as group
parameters. In this case, the group could therefore be represented
in a simple manner by the objects of the group with the lowest
time-to-collision and/or the shortest distance to the own
vehicle.
[0030] It is furthermore possible to divide up the preprocessing
even further and, where appropriate, distribute it among further
control devices in order to incorporate further elements, such as a
data filtering, a first situation evaluation or the like.
[0031] Even if, according to the invention, a different number of
classes of relevance is essentially possible, it has proven to be
particularly advantageous to divide the received data into three
classes of relevance, wherein the division can be carried out,
according to the selected criteria, already in the first receiving
control device or step-by-step in different receiving control
devices. A clear structuring and allocation of different processing
steps for the often very broad range of possible received data from
different objects can thereby be achieved.
[0032] A first class with the highest possible relevance level, a
third class with the lowest possible relevance level and a second
class with a medium possible relevance level can be formed here.
According to an aspect of the invention, the division of classes of
relevance is not restricted to three. The second class with a
medium possible relevance level is then further divided, wherein,
where appropriate, the boundaries to the first and the third class
can be shifted. The following explanation does not therefore apply
only to the specifically described three classes of relevance, but,
according to an aspect of the invention, also to more classes of
relevance, wherein the features described for the first and the
third class apply in each case to the class of relevance with the
highest and lowest possible relevance level. The criteria for the
categorization or sorting into the different classes of relevance
are suitably adapted in the case of more than three levels. One
criterion that is particularly suitable according to the invention
for the division into classes of relevance is the
time-to-collision, which, where appropriate, can be used in
conjunction with further criteria for the sorting into the
different classes of relevance.
[0033] The first class with the highest relevance level relates to
the immediate vehicle surroundings. This can be determined in a
specific example of the application of the method according to the
invention by the distance between the own vehicle and the object
from which the received data in the C2X communication were
transmitted. The distance as previously described as the linear
distance between the own vehicle and the object therefore defines a
radius around the particular own vehicle, within which information
from the C2X communication is always categorized as relevant in the
preprocessing. The time-to-collision, which takes into account the
distance with the speed of the object and/or the relative speed of
the object in relation to the particular own vehicle, can also be
used as a further criterion for received data. An appropriate limit
value for the first class may, for example, be a time-to-collision
of two seconds. In the preprocessing, in particular, no further
data and information are used according to the invention for the
categorization into the class with the highest possible relevance
level for the sorting into this class of relevance, and, in
particular, no assumptions are also made concerning the road, the
route of the object on the road or the driver behavior so as not to
delay the processing of these, in some cases time-critical, data
due to the preprocessing according to the invention. Where
appropriate, it can even be provided according to the invention to
further process these data directly and prioritize them in the
processing of the communication stack according to their high
priority, which is allocated to the data of this first class of
relevance. Technically, this can be produced, for example, by an
interrupt, which interrupts the normal (serial) processing of the
communication stack when the corresponding data in the first class
of relevance are present and inserts these data from the first
class of relevance, i.e. with the correspondingly highest priority,
into the processing of the communication stack or forwards them to
the safety control devices.
[0034] The second class, with the medium relevance level, relates
to relevant objects which may have an influence in the near future
on driving behavior and on the safety of the own vehicle, without
being directly safety-related. The distance between the vehicle and
the objects transmitting the data can be used as a criterion for
the categorization into the second class, wherein the radius or
distance of the surrounding area formed around the own vehicle is
greater than in the case of a sorting into the first class. As a
result, a short distance between the vehicle and the object can be
defined which, however, exceeds the immediate vehicle surroundings.
Furthermore, the time-to-collision, which, for example, is up to
five seconds for this class, can be used as a further criterion for
the sorting into this class of relevance. All objects of which the
time-to-collision with the own vehicle is between two and five
seconds are therefore also sorted into this second class of
relevance.
[0035] In addition, the objects which are still located within the
coverage area of the environment sensor system, for example a radar
sensor present in the vehicle, can also be included in the sorting,
insofar as an environment sensor system of this type is present in
the vehicle. Furthermore, data can also be sorted into this second
class of relevance on the basis of assumptions relating to the road
(highway, junction, rural road, road in built-up areas) and/or
assumptions relating to the driving behavior of the own vehicle
and/or the object. However, these objects additionally counted to
supplement the second class are preferably not formed in the first
control device, i.e. the receiving control device, but in a
downstream control device.
[0036] More distant objects are categorized into the last, in the
example described, third class with the lowest possible relevance
level. All objects which are not sorted into the other classes of
relevance can be categorized into this class of relevance with the
lowest priority. The data of these objects can be significantly
more intensively evaluated and/or combined in the preprocessing,
but preferably in further downstream control devices so as not to
overload the vehicle's own assistance systems due to a multiplicity
of C2X messages. Particularly in this class of relevance, it is
appropriate to combine data of different objects into a group. An
example of objects combined in this way may, for example, be group
information with the parameters "4 vehicles at position XY, group
speed 20 km/h, tailback". No dynamic prediction and/or trajectory
are preferably then determined for these objects. However, group
data of this type may, where appropriate, be linked to an object
from the medium (second) class of relevance which, for example,
constitutes the representative of this group nearest to the own
vehicle, for which a dynamic prediction or trajectory determination
is then possible.
[0037] A division of the data into the different classes of
relevance is then particularly simply possible if the classes of
relevance in each case cover a collision period. Here, it can be
provided that the collision period is disjoint. Alternatively, the
collision periods in the boundary area between two classes of
relevance may also overlap, so that the data in the boundary area
belong to two classes of relevance. This enables a redundancy in
the data processing and the different processing of the data in
different evaluations. In this connection, it is also conceivable
that one class of relevance partially or completely contains the
data of another class of relevance. A fast response to the data is
thereby possible, e.g., by bypassing a dynamic prediction, and the
dynamic prediction is carried out in parallel through the
preprocessing of the other class of relevance.
[0038] Furthermore, according to another aspect, the invention
relates to a communication system for data reception in wireless
vehicle-to-surroundings communication (C2X) between individual
communication participants, wherein the communication system is
provided in a vehicle and has different control devices with,
preferably in each case, a computing unit. The communication system
of the vehicle is configured in particular for participation in
wireless vehicle-to-surroundings communication (C2X) and can
therefore communicate in particular with other vehicles
participating in the C2X communication and stationary participants
in C2X communication, known as Road Side Units (RSU). Furthermore,
the computing units in the control devices are configured to carry
out the previously described method or parts thereof.
[0039] The invention also relates accordingly to a computer program
product with program code means which are stored or are storable on
a computer-readable data medium in order to carry out the method as
set forth herein, if the program product is installed and run on a
computing unit.
[0040] For faster and effective processing of data received in the
C2X communication, the present invention proposes to subject these
data to a preprocessing which may be divided, in particular, among
a plurality of control devices and which runs in parallel with the
processing of the normal communication stack, i.e., integrated into
or being related to the latter. In that the preprocessing according
to the invention is divided among a plurality of positions within
the communication stack, the processing of the communication stack
can be influenced by the preprocessing and, in particular,
individual steps of the preprocessing in order to be able to
process quickly and reliably a large volume of receiving data from
the C2X communication. For this purpose, it is provided according
to an aspect of the invention to divide the data for structuring
and/or the objects transmitting data in the preprocessing into
different classes of relevance. This sorting into classes of
relevance enables, in a simple manner, the data of different
objects to be preprocessed differently and to be incorporated into
the communication stack according to their class of relevance or to
be forwarded to the corresponding destination control devices. The
advantageously provided division among a plurality of control
devices allows smaller and less conductive control devices to be
used, which also do not all have to meet a high safety standard
(SIL level).
[0041] A preferred criterion for the sorting into classes of
relevance, where appropriate in conjunction with further criteria,
is the time-to-collision, which, in a simple manner, combines the
distance and the speeds or the relative speed between the own
vehicle and the object into a possible time-to-collision. This
time-to-collision is suitable, in particular, for an initial
classification. The receiving range of the environment sensors may
be a further criterion according to the invention for the decision
concerning the sorting or division of the data into different
classes, since data received from the receiving range of the
environment sensors can be qualitatively improved according to the
invention through a sensor fusion. Depending on the allocated class
of relevance and/or priority, which, for example, also enables a
sorting of the data or objects within the classes of relevance, the
objects or the data of the objects can be divided among different
applications. Due to the preprocessing, it is thus possible
according to the invention, even at an early reception stage, to
divide the different data appropriately and forward them to
suitable applications or to the control devices running the
applications. It is also possible to make further steps of the
preprocessing dependent on the sorting into classes of relevance in
a preceding step of the preprocessing.
[0042] If sufficient time is available for the processing, i.e. in
particular for data of objects which are sorted into a low or the
lowest class of relevance, it is also possible, according to an
aspect of the invention, to combine a plurality of objects into a
group and further process them with group data. Due to the
concentration and combination of the individual data into group
data, the volume of the data to be processed in the vehicle system
is significantly reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] Further advantages, features and possible applications of
the present invention can be found in the following description of
example embodiments and the drawings. Here, all described and/or
graphically presented features individually or in any combination
form the subject matter of the present invention, also
independently from their combination in claims or their
back-references. In the drawings:
[0044] FIG. 1 is a flowchart with the progression of the method
according to the invention for data reception in
vehicle-to-surroundings communication in a vehicle communication
system according to the invention according to a first
embodiment;
[0045] FIG. 2 is a schematic diagram of an example of a traffic
situation at an intersection, which is recorded and processed by
the method according to the invention;
[0046] FIG. 3 is a schematic diagram of an example of a traffic
situation on a highway, which is recorded and processed by the
method according to the invention;
[0047] FIG. 4 is a flowchart with the progression of the method
according to the invention for data reception in
vehicle-to-surroundings communication in a vehicle communication
system according to a second embodiment; and
[0048] FIG. 5 is a flowchart with the progression of the method
according to the invention for data reception in
vehicle-to-surroundings communication in a vehicle communication
system according to the invention according to a third
embodiment.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
[0049] FIG. 1 shows schematically a communication system 1 of a
vehicle with control devices 2, 3 and 4. The control device 2
represents a receiving control device to which the antenna (not
shown) with the transmitting and receiving electronics is
connected. In the receiving control device 2, the received data are
incorporated into the communication stack processing of the
communication system 1, which performs the process of the physical
decoding of the data received by the antenna through to the
processing and transfer of the data to individual applications in
application modules 5, 6, 7, 8 and/or 9 according to the
specifications of the communication protocol. According to an
embodiment of the invention, this communication stack processing
operation runs in parallel in the control devices 2, 3, 4 and,
where appropriate, the application modules 5, 6, 7, 8, 9 or their
computing units (not shown). The control devices 2, 3, 4 and the
application modules 5, 6, 7, 8, 9 can also be provided in one unit
with a common computing unit.
[0050] Following the reception of data, the communication stack
processing takes place at least to the extent that the received
data are present as digital and therefore further processable
values. Subsequently, during the preprocessing according to the
invention, a categorization or sorting of the data or transmitting
objects into reference classes takes place in the receiving control
device 2. For this purpose, the distance between the own vehicle
and the object is determined from the position data of the
transmitting object, which are contained in the values of the
received data, and the position data of the own vehicle, which are
known in the receiving control device 2, for example through
received signals of satellite-based location information or through
a different module via a communication network within the vehicle.
Furthermore, a possible time-to-collision is determined via the
speed of the own vehicle and the speed of the object. Here, from
the distance and the positions of the vehicles and also the
direction of the speed, known, for example, through transmission of
the individual coordinate components of the speed in the coordinate
system used is taken into account.
[0051] If the distance and time-to-collision are below predefined
threshold values for the first class of relevance 1 with the
highest relevance, the data or objects are allocated to the class
of relevance 1. If the distance and time-to-collision are above the
threshold values for the first class of relevance 1, but below the
threshold values for the second class of relevance 2, the data or
objects are allocated to the second class of relevance 2. Other
objects are allocated to the class of relevance 3 with the lowest
relevance or, if it is already certain that they are no longer
used, are already rejected here.
[0052] The objects in the class of relevance 1 are then further
processed with highest priority, since these objects present, where
appropriate, a direct risk to the own vehicle. The preprocessing is
ended for these objects and the processing of the communication
stack is concluded. This is shown in FIG. 1 by the double arrow,
wherein the conclusion of the communication stack processing may
also include, for example, according to the invention, a check on
the data security or data authenticity particularly if necessary or
required.
[0053] These data are subsequently forwarded immediately to the
application module 5 with a driver assistance system and/or a
driving safety system, which suitably further processes the data
and instigates the necessary measures. These measures may include,
for example, the instigation of automatic braking. Since these
applications of the application module 5 relate directly to the
safety of the vehicle, the data of these objects must be processed
in control devices with a correspondingly high safety level (SIL
level). These data are not therefore subjected to a prediction in
the preprocessing, but are forwarded as quickly as possible to the
correspondingly safe control devices.
[0054] The first step of the preprocessing in the reception control
unit 2 is therefore restricted to a recognition of the relevance of
the data and the fastest possible forwarding of the most relevant
data to the final processing application module 5 in order to
achieve the lowest possible latency of the data of these relevant
objects. Where appropriate, during the sorting of data into the
class of relevance 1, an interrupt can even take place in the
communication stack processing, so that these data can be further
processed immediately in the communication stack and can be
forwarded as quickly as possible to the application module 5.
[0055] Conversely, the objects in the classes of relevance 2 and 3
are initially further processed in the preprocessing. So as not to
burden the computing power of the receiving control device 2
unnecessarily, the further steps of the preprocessing are carried
out in the downstream control device 3.
[0056] The objects already categorized by the receiving control
device 2 into the second class of relevance on the basis of their
distance and/or their time-to-collision are allocated immediately
to class and are further processed as described below. Conversely,
objects not sorted into the second class of relevance 2 are
subjected to a further categorization into classes of relevance.
For this purpose, the coverage areas of environment sensors of the
own vehicle are additionally considered under ideal conditions,
which occur in the control device 3 as suitably parameterized
information. Objects which, according to their position indications
contained in the data, are located in this theoretical coverage
area, are additionally categorized into this class 2.
[0057] In a further preprocessing in the application module 6, a
sensor fusion, for example, can then be carried out if the objects
identified in the C2X communication are also detected in
environment sensors of the vehicle, for example a radar sensor. As
a result, the data processed in the communication system 1 of the
vehicle are not only qualitatively improved, but are also condensed
in the sense that different information elements are merged into
one object. This simplifies and speeds up the further processing in
downstream applications, since the multiplicity of individual data
elements is reduced.
[0058] Furthermore, an attempt can be made in the application
module 6 in the preprocessing according to the invention to improve
the position accuracy of data for the individual objects in that,
for example, the data are compared with other data in the coverage
area and/or in that a suitable data filtering takes place. In
addition, a dynamic prediction can take place in the preprocessing
according to the invention, taking into account map and road
information present in the application module and/or a direction
evaluation of the individual take place objects in relation to the
own vehicle. This enables a simpler tracking (temporal and spatial
tracking) of an object for downstream safety devices. Transferred
data, such as, for example, a bend in the direction of movement
and/or acceleration or deceleration of the object, can also be used
here. To conclude the preprocessing in the application module 6 and
end the communication stack processing, the data of the objects are
made available to a vehicle application module 7 which may also
involve, for example, a driver assistance system (which may also be
identical to the driver assistance system 5). The application
module 7 may also be a location and/or navigation module or any
given further application in the vehicle which uses data from the
C2X communication.
[0059] The class 3 data and/or objects are finally forwarded to a
further control device 4 in which a further and concluding
preprocessing is carried out by the application module 8. This last
step of the preprocessing may consist in abandoning data
categorized as completely irrelevant and terminating the processing
of the communication stack for these data so as not to consume
memory and computing time resources unnecessarily in the control
devices 2, 3, 4 and downstream applications. A further application
may involve combining groups of objects from which data are in each
case present and treating them as one object in order to reduce the
data volume. Applications for this purpose have already been
explained and can also be found in the driving situations described
below with reference to FIG. 2 and FIG. 3. It can be provided
according to the invention that no dynamic prediction or sensor
fusion is carried out for the objects in the class of relevance 3,
because the knowledge gain is not normally worthwhile. However, the
information obtained, insofar as it is not rejected, may in any
event be forwarded to other applications, for example an
application module 9 designed as an infotainment or mobility
module.
[0060] Since data are typically permanently received, but the
individual applications access the data with a certain time loop,
the data must, where appropriate, be temporarily stored in the
control devices 2, 3, 4 or other memories. For this purpose, it is
appropriate to store the data according to classes of relevance
and, where appropriate, supplementary priorities, but otherwise
chronologically. Where appropriate, the time difference between
reception and retrieval can be compensated by means of a short-time
prediction, preferably by the downstream application.
[0061] The communication system 1 described in FIG. 1 is an example
and represents one embodiment. The functions of the individual
components described in connection with this embodiment are not
restricted to an arrangement of the components in precisely this
form and can also be used in modified forms, in each case
separately, as a contribution according to the invention.
[0062] FIG. 2 shows a traffic situation at an intersection. The own
vehicle F and other vehicles or objects O, which are numbered
sequentially in the representation for a simple reference, are
located on roads 11, 12 shooting at the intersection 10.
[0063] The own vehicle F moves on the road 12 toward the
intersection 10. The movement range attained within a predefined
short time-to-collision is drawn with shading as the collision area
KF of the own vehicle. The vehicle O1 moves accordingly on the road
11 toward the intersection 10. The collision area KO1 of the
vehicle O1 is similarly drawn with shading. Since these two areas
KF and KO1 overlap one another, the time-to-collision for
categorizing the object into the first class of relevance 1 is
understepped. This object is therefore categorized into the first
class of relevance 1 and its data are forwarded immediately to the
application module 5 with the driver assistance system.
[0064] The vehicle O2 moves on the road 12, but in the opposite
direction to the own vehicle F, toward the intersection 10. The
corresponding collision areas are not included in the drawing for
the sake of clarity. However, due to the movement of the two
vehicles, these collision areas also overlap one another within the
threshold values applicable to the sorting into the second class of
relevance. The object 2 is therefore sorted into the second class
of relevance. In the further preprocessing in the control device 3,
a dynamic prediction of the object O2 is attempted. Furthermore, if
the object O2 is detected by a vehicle environment sensor of the
own vehicle, a sensor fusion is carried out. A reliable tracking of
the object O2 is thus possible. If the driver of the own vehicle F,
indicates, for example, by means of a flashing signal, that he
wishes to turn left into the road 11, a warning can be given
regarding the vehicle O2 in the oncoming traffic.
[0065] The vehicles O3 to O6 are stationary in the oncoming traffic
on the road 12, because they wish to turn left into the road 11 and
must consider the own vehicle F, which would have priority if
driving straight on. Since these vehicles O3 to O6 are stationary
due to the traffic conditions, their collision areas do not overlap
with the collision area of the own vehicle F for either the first
or the second class of relevance. The distance between the own
vehicle F and the vehicles O3 to O6 is also so great that the
latter are not to be categorized into the class of relevance 2.
These objects O3 to O6 are therefore sorted into the class of
relevance 3.
[0066] In the application unit 8, it is established, through
evaluation and comparison of the data of the objects O3 to O6, that
these objects O3 to O6 have common characteristics. These objects
O3 to O6 are therefore combined as the group G, which is
represented in this case in an appropriate manner by the object as
the object nearest to the own vehicle. Due to the combination, the
data volume to be processed in the communication system 1 of the
vehicle can be significantly reduced.
[0067] FIG. 3 relates to a traffic situation on a highway 13, of
which only one direction of travel is shown with the lanes 13.1,
13.2 and 13.3. The own vehicle F is located in the second lane
13.2. For the own vehicle F, the collision area KF determining the
categorization into the first class of relevance is also shown with
shading. The vehicles O1 and O4, from which C2X notifications are
also received in the communication system 1 of the own vehicle F,
are traveling in the same lane 13.2 behind or in front of the own
vehicle. The collision areas KO1 and KO4 of the former vehicles are
also included accordingly in the drawing. The vehicle O2, which is
just executing a lane change into the lane 13.2, is traveling in
the lane 13.1, slightly offset in front of the own vehicle F. The
collision area KO2 is also included in the drawing for this vehicle
O2.
[0068] Since the collision areas KO1, KO2, and KO4 overlap with the
collision area KF of the own vehicle F, the objects O1, O2 and O4
are sorted into the class of relevance 1. According to the
invention, the driver assistance system 5 therefore receives the
data of the objects O1, O2 and O4 particularly quickly and can
inform the driver as early as possible of the recognized and
dangerous lane change of the vehicle O2.
[0069] This would essentially also apply to the object O3, which
does not, however, participate in the C2X communication and is
therefore not taken into account in the method according to the
invention.
[0070] The vehicles O5, O6, O7, O8, O9 and O10 are located, in
relation to the own vehicle F, outside the relevant distance and
outside the relevant time-to-collision. These objects O5 to O10 are
therefore sorted into the third class of relevance. In a further
preprocessing of the application module 8, it is recognized that
the vehicles O9 and O10 are traveling in a different lane 13.1. The
data of these objects O9 and O10 are therefore categorized as
irrelevant and are rejected. For the objects O5 to O8, it is
recognized in the preprocessing in the application module 8 that
these vehicles are traveling in convoy in the same lane 13.2 as the
own vehicle. These vehicles are therefore combined into a group G
and their data are represented by the object O5, which is the
nearest of the objects O5, O6, O7, O8 of the group G to the own
vehicle.
[0071] FIG. 4, in a schematic flow chart, highlights a further
variant of the invention, which can also be combined with the
variant described with reference to FIG. 1.
[0072] According to FIG. 4, it is provided that, following the
reception of the data via the antenna and decoding of the
transmission signals 14 in a first step of the communication stack
processing, which is indicated by a double arrow, the data are also
further evaluated in the receiving control device 2 integrated into
the antenna unit (not shown) on the basis of their distance to the
own vehicle. Following this relevance evaluation 15, only the
relevant data are further processed in downstream control devices
and the communication stack is further processed.
[0073] For this purpose, a further processing of the communication
stack is provided in FIG. 4 through an authentication 16 of the
received data. The security of the objects and/or data is therefore
checked in a security module 17 only if they have been evaluated as
relevant to vehicle safety (e.g., due to a possible risk of
collision) or mobility (for example, due to an indication of a
tailback).
[0074] Conversely, if the objects are not categorized as relevant,
they are given the evaluation "Security not checked" or are
rejected. This procedure significantly reduces the complexity with
which the data authenticity check is normally associated.
[0075] Only in a step downstream of the authentication 16 are the
data further checked in more detail in application modules and are
sorted into data or objects which are highly relevant, critical or
medium-relevant, or to be watched. The critical objects are
immediately forwarded as described to a corresponding safety
application and the objects to be watched are earmarked, where
appropriate, for tracking in a next processing pass. This is not
shown further in FIG. 4.
[0076] Finally, it is possible that the data categorized as
irrelevant are nevertheless post-processed, insofar as the
processing does not require any resources in terms of memory space
or computing time which are required elsewhere. If data not yet
authenticated prove to be relevant in a post-processing of this
type, these data will be reclassified as relevant and then
forwarded to the authentication 16. This is indicated by a dotted
arrow within the relevance evaluation 15.
[0077] FIG. 4 shows how the communication stack processing and the
preprocessing according to the invention of the data received in
the C2X communication are interlocked with one another.
[0078] In a further exemplary embodiment, shown in FIG. 5, and also
combinable, where appropriate, with the previous exemplary
embodiments, the data received in the C2X communication are divided
or sorted into classes of relevance directly on the receiving
control device 2, wherein the following class of relevance
designations are provided: "unimportant", "relevant to mobility",
"relevant to information", "relevant to safety". The data in the
unimportant class are not forwarded or further processed. The other
data are forwarded to different, downstream control devices 18,
wherein, where appropriate, only one downstream control device may
also be provided.
[0079] This rough classification is used in the downstream control
devices 18 to validate the data. In the validation, a check can be
carried out to ascertain, inter alia, whether the present data of
the objects are consistent with the history of the objects. The
validation of the data is controlled here in such a way that
safety-critical objects are subjected to more elaborate methods and
are analyzed more precisely than mobility-related objects.
[0080] The validation can also be carried out in different control
devices, which have a corresponding safety level (ASI level) for
the data classes, so that safety-critical data are processed in
control devices that have a low probability of failure.
[0081] If the relevance evaluation of the data changes in the
subsequent processing, the data can be fed in each case to the
corresponding control devices, as indicated by the double
arrows.
[0082] Thus, while there have shown and described and pointed out
fundamental novel features of the invention as applied to a
preferred embodiment thereof, it will be understood that various
omissions and substitutions and changes in the form and details of
the devices illustrated, and in their operation, may be made by
those skilled in the art without departing from the spirit of the
invention. For example, it is expressly intended that all
combinations of those elements and/or method steps which perform
substantially the same function in substantially the same way to
achieve the same results are within the scope of the invention.
Moreover, it should be recognized that structures and/or elements
and/or method steps shown and/or described in connection with any
disclosed form or embodiment of the invention may be incorporated
in any other disclosed or described or suggested form or embodiment
as a general matter of design choice. It is the intention,
therefore, to be limited only as indicated by the scope of the
claims appended hereto.
* * * * *